The Strange case of a Victor HC-95(a) 512KB! | MSX Resource Center (Страница 5/5)

By popolon_

Champion (420)

07-06-2022, 22:20

In your pcb there is also that 5th rom chip, toshiba tc541000p, 128Kbyte mask rom.

By retrocanada76

Hero (575)

07-06-2022, 22:51

right so the victor-95 wiki slots is wrong then right ? there is no kanji on them. Strangely the manual doesn't mention it too

By mars2000you

Enlighted (6559)

08-06-2022, 00:35

The Kanji-ROM is confirmed here:

http://usbsecretbase.michikusa.jp/hc-95/index.html

Btw, this ROM is not in a slot.

By gdx

Enlighted (6437)

08-06-2022, 02:35

And it was already confirmed a long time ago. It says Kanji JIS-1 in the ads.

gdx wrote:

I think is not possible because pins /DR, /ME, /IOE and /REF replace the pins /M1, /MREQ, /IORQ and /RFSH. HD64180 is a z180 whose hardware is closer to z80, but I was talking about software compatibility.

I reversed the notations. This is the HD64180 that have pins /DR, /ME, /IOE and /REF.

https://pdf1.alldatasheet.net/datasheet-pdf/view/120400/HITA...

By retrocanada76

Hero (575)

08-06-2022, 02:53

but these pins are analogues to the z180 just the names that seem to change and the Z180 seems to boot in hd64180 mode you need to change the I/O 0x3E to 0x000xxxxx to get into Z80 mode.

By gdx

Enlighted (6437)

08-06-2022, 12:25

For me, the HD64180 is the first Z180.

retrocanada76 wrote:

but these pins are analogues to the z180

They seemed to work differently when I looked at the timing diagrams.

But okay, so the HD64180 is in fact almost a Z180 (Z80180) that was called "Super Z80". The two chips are very close because the Z80180 is based on the HD64180 design. Zilog only made a few changes. OPcodes are same. It seems possible to replace the HD64180 by Z80180 but it needs to be configured to operate as the HD64180. Although, the support for the 68 series bus is perhaps an obstable.

Both don't support IXL/IXH and IYL/IYH, and if the prefix DD or FD is used in front of an instruction having the opcode CB and which does not refer to (HL), it will be executed as a NOP.

By msxtrd

Champion (277)

28-09-2022, 20:53

Stumbled just upon some more HC-90/95 reading . Just sharing.... http://d4.princess.ne.jp/msx/other/hc-95/index.htm

By msxtrd

Champion (277)

28-09-2022, 20:57

I like the quote down below in the document "By the way, the HC-90/95 have continued to be sold for a long time as teloppa and the above-mentioned incomprehensible system, and in fact, they were sold even after the A1GT sales ended. "